Chek-soh (Eng-gí: notochord) sī só͘-ū chek-soh tōng-bu̍t ê kiōng-tông te̍k-sek, sī chi̍t tiâu nńg ê koaiⁿ-hêng bu̍t, ū chi-chhî sin-thé ê chok-iōng. Tī toā-hūn chek-chui tōng-bu̍t, phoe-thai sî-kî ê chek-soh āu-boé ē hoat-tián chò chek-chui ê chú-kàn.